Speaking to The Daily Telegraph on Friday, the young musicians revealed they were stuck on the tarmac of Chicago's O'Hare Airport when they heard the news.

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'We had McDonald's and champagne ... It was an odd mix': 5SOS boys reveal the casual way they celebrated their album reaching number one on the American Billboard chart (Pictured from left is Luke Hemmings, 21, Calum Hood, 22, Ashton Irwin, 23, and Michael Clifford, 22)

'We had McDonald's and champagne. It was an odd mix,' frontman Luke Hemmings told the publication.